If you want a customisable device get a nook touch and root it. Its basically becomes an eink android tablet the author of coolreader the reading software in openinkpot supports nook touch so all its options are accessible.

that is shurly a way to look into. Thaks for that.
Since you have the device (and rooted, as I guess), some questions:
(since I#m unused to andriod)

I want basicly: read english books and have (or can install) a good dictionary (en-germ), which works by tabing the word to translate. And be able to take notes inside the book (for making notes/corretions to the stories my daughter writes.
Have you tested things like that?